Magnetic core control circuit for elevators



Feb. 16, 1965 a. THIRUP MAGNETIC CORE CONTROL CIRCUIT FOR ELEVATORS Filed July 3, 1962 5 Sheets-Sheet 1 INVENTOR Gunnar Thirup ATTORNEYS Feb. 16, 1965 s. THIRUP 3,159,606

MAGNETIC CORE CONTROL CIRCUIT FOR ELEVATORS Filed July 3, 1962 5 Sheets-Sheet 2 cm. A

INVENTOR Wf/QMQML ATTORNEY Feb. 16, 1965 G. "n-uRuP 3,169,606

MAGNETIC CORE CONTROL CIRCUIT FOR ELEVATORS Filed July 5, 1962 5 Sheets-Sheet 3 t t, t t t,

aw/MM ATTORNEYS Feb. 16, 1965 a. THIRUP 3,169,606

MAGNETIC CORE CONTROL CIRCUIT FOR ELEVATORS Filed July 5, 1962 5 Sheets-Sheet 4 1 CP7 H n cm. A i 2 Fl FIGA INVENT OR Gurmar Thi d/ e ddwb ATTORNEYS Feb. 16, 1965 G. THIRUP MAGNETIC com: CONTROL CIRCUIT FOR ELEVATORS 5 Sheets-Sheet 5 Filed July 3, 1962 V! Sh w w h h M. .md HV M M. 3 mu \I, q HVAH FIG]- INVENTOR Mia/(2 8% ATTORNEYS I error correction.

limited States iatent The driving plant for lifts consists of the motor with gears, winch and brake, viz. the parts which produce and transfer the required mechanical energy; further the plant "comprises contactors operatingsaid parts, and a control circuit arrangement which processes the publics calls and, if desired, also the signals determined by a fixed 'programme and converts such signals into operating orders for the contactors. The knowncontrol circuit arrangements are cornposed of relays, push-buttons, switches, etc., i.e. of members with mechanically moved parts which are subject to wear; and comprising contacts whose contact resistance is dependent on the condition of the surface and on the contact pressure, i;e. factors which vary with time and require a continuous attendance and inspection if disturbances are to be avoided. Further, mechanically moved parts create noise which may be inconvenient in dwelling houses andofiice buildings. a

It is therefore a general object of this invention to improve these conditions in a control circuit arrangement for lifts and other plants usedfas a conveyor, for example, in

parking houses, storage buildings,.etc.', where the load is to be moved vertically or horizontally from and to definite places, and his therefore suggested according to the invention to replace therelays of known control circuit arrangement by electronic elements such as transistors, flip-flops, memory'cores, etc. f

According to the invention, having horizontalrows and vertical columns memory cores are to be arranged in a matrix all cores receiving information regarding a floor ,being arranged ina horizontallrow. Each'horizontal row is associated with circuit passed byinterrogatingpulses which occur as a function 'oftime typicalfor each row and are of such sizeth'at each .pulseis capable or bringing a core from the state of saturation (l-state) orginating from an information pulse to the other state .of saturation train appearing from FIG. 2 wherein thetrains I 12, etc.

a which travels between four floors.

Patented Feb. 16, 1965 The diagram shown in FIG. 1 describes the invention in its simplest form and, consequently, relates to a control circuit arrangement for a lift, comprising a cage The control circuit arrangement consists of matrix A comprising memory cores, of an interrogating unit SP, which generates interrogating pulses and transmits such pulses to the matrix A, and of a logical unit LE where the pulses transmitted from the matrix areprocessed and re-transmitted in the form-of operating orders to the contactors of the lift.

The memory cores in the matrix A are arranged in horizontal rows 1, 2, 3 and 4 and in vertical columns 101, 102, 103 and 104, each core being designated by the number of the column and the row, e.g. 191,4 or 192,1. In each the rows l-4 such cores are arranged as receive information regarding a floor, for examplerow No. 1 is assigned to floor No. 1, etc. mitted'in the form of current pulses through the lines L L etc. to the corresponding cores 101,4, 161,3

etc. Information of the same nature is stored in one and the same column; the publics orders for example, are

stored in column 101 by the cores of the rows corresponding to the floors towhich thecage is to be moved,

the cores being magnetized in a positive sense, i.e. the

cores'are brought from theoriginal O-state into the l-state.

stopped at-the floor in question, i.e. the next following floor reckoned from the floor above or below. -At the top floor, the core in column-lO2 :may consequently be omitted; and'in the bottom floor, the core incolurnn 103 may be omitted. I

A line L L L L respectively,,passes:through all of the cores. These'lines are continually passed by apulse train, which is typical for each row, the course of said represent the pulses of rows l, 2, etc. Thejpulses emitted (O-State); When the core is brought from the l state to theO-State, apulse is generated in a circuityvhich is common to all cores subject 11011116 same type ofinformation regarding the differentfioors and placed in a vertical colurnn; said; pulse determining alone or in commoniwith other pulses the nature ofthe operating-order.

"The'invention willby wa'y lcifexample be explained in the following with reference-,to/the -ac'con'ipanyingidraw- 'ing,in-which l 1 1 FIG. 1 shows a circuitydiagramffor ai cont circuit arrangement fora liftcage, i

Frogs shows a timeidiagramaof anmsaaa aan pulses occurring periodically in the'control :ci'rcuit. ar- -,.,rangementofFIG.1,- I c FIG. 3 shows the mutual time displacernent 10f the p I l the pulses occurring in connection'with Man interrogating pulse whensaidpuls freverse's'ithefnia'g- .netization ofa corein thematrix;

' .IG. 4 shows 1 FIGQS) shows 'an arrangefment for t "fromtheliftcageto theliftsh'aft; v V 1 EFIG, 6*shows' acircuit for an arrangement according tb'FIGgS, W FIG. 7 shows acircuitarrangement according. to the samesprinciple as the on'eish'own in'FlG. 6,"however, with ransferring "signals frequency, but pul'ses'oflsubsequent rows are delayed 21 certain period of'tiine' t, forexamplel ms. with respect to each other. Besides the pulse trains l -i -there is a pulse train "1;; which is not assignedto any floor or matrix row and which has a course corresponding to a row lying below the lowermost matrix row. 1 The tirn'ediiference'between the If; pulse and the. pulse no f the topmost row is the sameas that betweenthe other pulse rows, narnely t. Throug'h'the cores 'ofneach-x row in'FIGfl are passed further conductors 1 lg, l3;- l.;, which are Passed-iby 'cur-- :1 rent pulses i ,,i =andyi These pulses;have,f='aswill appear fr m FIG-QZ, theesame frequencyas thepulses, I a-I andlopposite sign andjare' fo'f such,a.magn itude*that .two concurrent pulses of the same value :are..-capable of evs-angina, magnetization of a core .yvhilefonepulsef alone isi notcapable thereof. Suchcurrentis therefore .caliedia half-sizecur'rent.-.It,is.xpedientto'protiuce the 6 5fii-pu1ses byfdiiferentiatingljI-pulses and tosampl'igfyfthe pulses "occurring: of-theLpulses; r {As will appear from FIGxl, pairs of conductorsK er the cores {in lc'olumns' 101, 1502 and 103,; while prn p I one conductor Kmgis' passedthrough the magnesium 'f .fiIn' the icbnduetors:ofzthe rK-type thereiis induced The information is trans as acons'equence of the disappearance,

a voltage pulse when the state of magnetization of a core in said column is reversed by an I-pulse, while the conductors of the k-type are passed by a half-size current originating from the Logical Unit LE and caused by voltages in the K-conductors, which half-size current shall occur simultaneously with a half-size current in a matrix row in order to bring a core into its l-state.

FIG. 2 further shows a pulse train CP7, the period of time between subsequent pulses being t. The pulses of the pulse train CP7 are of positive sign, and are displaced in relation to the i-currents and the I-currents so that these currents cannot occur simultaneously with the CP7 pulses. The pulses CP7 are such currents as occur in the lines Lmlll etc. dependent on information coming from the exterior. In columns 102 and 103, CP7 pulses also occur with negative sign and thereby bring the cores from their l-state into their O-state. In this connection it is of importance that the reversal of the magnetization is effected more slowly than in the other cases, for which reason the curve shape of CP7 exhibits slower rise and fall than is true for the other pulses mentioned previously. Due to this measure the voltage induced by the reversal of the magnetization is reduced, further details as to this point being given below.

In the logical unit LE, there is also a train of voltage pulses CP4 which occurs with positive sign and the same frequency as the CP7 pulses. These pulses occur after the I-pulses have disappeared and after the i-pulses have commenced, and stop the current in the lines k k 103i 104- In the logical unit LE, there is also a current pulse train CP6 having the same frequency as CP7. The individual pulses of this pulse train CP6 start during the time interval wherein the pulses in the conductors k k km and k occur, and they terminate after these latter pulses have terminated but prior to the commencement of a subsequent I-pulse.

These conditions for the mutual phase-shift of the pulses are to be observed and are observed by the example shown in FIG. 3 for the time-course of the pulses. At the time t an I-pulse commences, as will appear from the top row in FIG. 3. If the core through which the I-pulse passes in column 101 is in its l-state, the pulse occurring due to the reversal of the magnetization produces a current i (FIG. 3, second row) in the conductor k The I-pulse terminates at the time t and thereby starts an i-pulse (FIG. 3, third row); the i-pulse terminates at the time i j At the time A; the pulse CP4 (FIG. 3, fourth row) occurs which stops pulse i The pulse P6 (FIG. 3, fifth row) commences at the time t and terminates at the time t the pulse CP7 (FIG. 3, sixth row) commences at the time i and terminates at the time t-;. The time interval t may as said above amount to 1 ms. and the moments t -t may be distributed according to a linear time scale as shown in FIG. 3, however, other displacements are possible as well, if only the conditions referred to in the explanation of FIG. 2 are fulfilled.

The logical unit wherein the pulses transmitted from the matrix are processed, consists substantially of eight are set by the pulses which are induced in the conductor of the K-type connected to the set-input s of each flip:flo'p.

The flip-flops are provided with a transformer to increase :each have a reset input r and voltage pulses (3P4 are supplied thereto from SP via a conductor'L The flip- 'Ti' flop FFlOl .is furthermore provided with an additional 7 reversed. I I

: .The flip-fiop FF4 is arranged so as not to react to the A. re-set input r, which is connected with an output conductor 0 from a core 104K in LE.

Connected to the output of the flip-flops PF 191, FF102 and FFHB are the previously mentioned conductors k k and k which each pass the vertical columns of the matrix as well as the cores 102K, 103K and 104K. Thus, the conductor k is passed through the cores 162K, 103K and IMK, the conductor k is passed through the core 102K, and the conductor k is passed through the core 163K so that the current pulses through the conductors will magnetize the cores in a positive sense. The conductor k connected to the output of flip-flop FFEM does not pass any column in the matrix and is passed through the core 104K so that the current pulse of the conductor will magnetize the core in the positive direction.

All flip-flop output conductors are connected to the minus terminal of a voltage source (not shown). The input conductors K K K are, as mentioned above, at their one end connected to the inputs s of the flip-flops, whereas their other ends, via a further conductor not shown, communicate with the other terminal of the input transformer, these other transformer terminals being connected to each other and likewise to all of the emitters of the flip-flops; in the following this junction is referred to as earth.

Each of the cores 102K, 103K and 104K is brought into its l-state by combinations of current pulses from FFltlt with pulses from FFltlZ, FFltlS and 1 1F104, respectively; however, 102K and 163K may be prevented therefrom by an inhibitor current through a conductor k which will be referred to later.

The core 104K is passed by a pulse current (0P6, FIG. 2) which will bring the core into the O-state each time an I-current has occurred in the matrix while the cores 162K and 103K are brought into their O-state by another current pulse (I FIG. 2) each time the bottom row in the matrix has been asked, i.e. has been passed by an I-pulse.

Dependent on the magnetizing state of the cores ltlZK, 103K and IMK, bi-stable flip-flops FFZ, FF3 and FF4 are controlled, which together with a mono-stable flipflop FFl transmit control orders to the operating system. In addition thereto FFZ and FF]. are controlled by pulses supplied through a line LS from the lift cage when it passes one of the points in the lift shaft indicating that the motor momentarily coupled is to be disconnected, and that the mechanical brake has to be actuated, if the cage is to stop at the floor in question. For this purpose the set-input s of FFI and the re-set input of FFZ are connected with LS, and the set input s of FFZ and the re-set input r of FPS are connected with a conductor 0 which extends through core 104K and is connected to earth. Pulses are induced in conductor 0 when the magnetization of core 104K is reversed. The s-terminal of P1 3 is connected with a conductor K extending through the.

cores 102K and 103K and being connected to earth; a voltage is induced in' connector K when the magnetization of one or both of the cores 102K and 103K is reversed. The

. input terminal 1 of FF4 is connected with earth by a conductor 0 which extends through-core 103K. A voltage is-likewise inducted in this conductor 0 when the magnetization of core 103K is reversed. The input terminal 2 of FF4 is connected with earth bya conductor 0 which extends through a. core 102K so that a voltage'is induced in conductor 0 when the magnetization of core 102K is pulses which are transmitted from the cores when they are brought from the O-state .to the l-state, and not to L l-state to its O-state, and is brought into its other position I when only the, other core is brought from its' l-state to react, either, when bothcores are simultaneously brought from the l-state'to the O-State, whereas it is .brought into its one position when only one core'is broughtfromits its O-state.

occurs and, aga

where are, to. stopped at' the next" ,however only act p transrnitsahalf-size' currentthrough th'eQconduCl and B15101 at,the;s,aine time sen ers half-s' i through the conductor {c 6 =.When,the cor li e n narnelyjthe call,

The output circuits of the four flip-flops are connected in the following manner: The output conductor k of FFl, the output conductor k of FFZ, and the output conductor k of FF3 are connected with a'common conductor k passing through the cores 102K and 103K so that the current in the conductor prevents the cores from being brought intiotheir l-state.

The output terminals of PET, FFZ, and FF3 are furthermoreconnected to conductors p p' p p respectively, whereas the output terminalsof FF4 and exclusively connectedto conductors p and p.;; theselast-mentioned conductors in turn are coupled with the operating system of the lift in order to re-transmit the respective orders to this system. v V

In the following it will be described how theplant is processing the received signals, of a lift having two travelling speeds. Supposed in a first instance, that an external call be given in orderto stop the travelling cage at the second floor. When thecage has reached adefinite point opposite the second floor the winch motor is to be changed from high speed-to low speed, called the creep- 7 ing speed, andonly when the cage has reached this speed,

. the cage isto be stopped at level with the desired floor. The procedure of changingto the lower speed is initiated in thefollowing manner. IThecall has the effect that a positiveCPT pulse of the conductor L of the core ltllfi brings the core into its l-state, thereby effecting a periodic reversal of the magnetization of the core, which process continues afterthe CPI pulses have terminated and, consequently, also takes place when the cage reaches the point in the lift'shaft where the change toslow motor speed has to be effected.

This process of reversal of the magnetization will be 1 explained at best by means of 'FIG. 4,-where the topmost row shows the pulse 0P7 coming from the exterior, via the conductor L This, pulse brings the core 161,2 into its l-state, and nexttime a current pulse I (FIG. 4,

2nd row) occurs the conductorrL the core is brought into its O-State, whereby-a voltage V (FIG 4, 3rd row) is induced in the. conductor K This voltagefpulse floor'at'whichthecage isto be stopped, isto be erased and braking has to beinitiated. The erasure is effected by FF101' being re-set prior to the occurrence of the current to overcome the magnetization originating from the two half-size currents from the flip-flops FF101 andyFFlM and moreover to bring the core into its O-State. The pulse generated by CP6 in the conductor 0 due to reversal of themagnetization of'the core 104K, re-sets FF101, and the core ltlLZ remains in its O-state until it is brought into its l-state by a CB7 current pulse through L The pulse in conductor 0 sets the flip-flop FF which via the conductor p transmits the order to couple the slow-speed motorand re-sets the flip-flop FFB which thereby gives-the order via conductor p to decouple the highspeed rnotor.

It .shouldbe noted that the core 104,2 like all cores in column 104 can only be set in its l-state so long as current pulses are coming from the lift shaft as the cores are not provided with magnetization lines corresponding to the lines k k k and they are not provided with the to corresponding magnetization pulses.

After the trans 'nission ofthe braking order and after B the cage-hasreached its creeping speed it istobestopped.

causes that the llip fiopFFlyll1 is seta nd transmits, with a little time delay according to the reactiontimes or: the core and the, flip-dope half-size current i101, (FIG,, 4, 4th

row) through theconductork b current pulse is terminated by the voltage pulse CPd (FIG. "4, 5 throw')' which resets FFltl-l. Priorto the occ'urrence of CR4, the:

l -pulse has terminated and thei pulse (HG; 4 ,6th'row) bringstheeore 191,2 into its l-state'.

theeore. is in its f lsstateluntill it,';in'a' manner whie t .be deslc'ribedilate'r, isbrou'ght into its permanent 1 -0-istate. It shouldbenotedithat the'sta'teof mag w i of none ofthe other -oores, neit11'er as these, cores haveohl be isbroug'tanto its lrstate'eachltime -the cagepassesfa e actuated, if "the .cage. is "to :be,

owinglflo or The brakes are 104K isjjthereby brought into its lestate'becaus ou ht s a 2w. jth s ar @01 3? This, rocess'isrepeated each timelan n-pn sef emn-s r;

petun a 101', w re at the same time more 0 Fumn" 1 which is associated with-i'the fioor inques nis I This-is vefiected in the following way. For eachfioor, consequently also for floor No. 2, means is provided in the 'shaft which cause a pulse to be transmitted to the conductorLS, when the cage is located at the place where the 0peration of .the' mechanical brake has to be started. This pulse re-sets FFZwhichvia the line 1 transmits the order ,tofjdecouple theimotorfirotating at creeping speed and to operate the-brake The ,sanie pulse sets, the mono-stable flipdldp This; flip-flop re-sets itself after some time in together with the curr'en -pulse i i i g which is chosenso great as to leave ,sutlicient time for unlo'ading andloading the cageprior to another start'which can take plac'ejonly' 'after the resetting of EFL sipre ou'slyunentioned -the position of the cage :is

' olpninslOZand 103 byithe'coresfincolumn l I p g b ought into their "tate when the cage is P i r r above thesmdlloor, and ,the co s 50;

e H incolumn 10; being ,breught into theirl-state when the cageis below thefsaid As long as the registered position of'thecage isrnot' alteredthere will as described inconnectionwith column 'l0l-,$be effected a,periodicalreversal of the magnetization f1 bringsthegjfcore ,in

: 'cage isjtravellihgi downwards thereb QiH b fi t e his t n w zz core belongingto the said floor fiofiritsjlstate ,when-the cage vtravels downwards, and

,the cage is travelling upwards, arrange ffthe' column'.,,,When the core =is' b rought eep'ness is so small that mevsnag 'lumns which are brought into {is obe regis ereein columhrl02, he pre-' ital-state" when the cage travels" up 7 in? ief a ee ,i 't haftesne esP s t ve h ct -ohms corest and thereby o:

By se alterations, arvoltag elpulse i induced,

-st'ate -to. its xi'll-state fltihe voltagelpulseYhas' a a hich'gleavesithe pulse' inefiectivefj"When Chang-.1

to O'takes lace, however, the pulse is eife'ctive 1 tfar'nplitude. Therefore the C P7 pulse 1 duced in the K conductor of the column which by reversal of the magnetization of the cores is not capable of producing an operative signal. In a corresponding manner the registration in column 103 is altered when the cage reaches a point below the floor. The poihts in the lift shaft where the registration is altered may expediently be the same points where the braking is to be initiated if the cage is to be stopped at the floor. Therefore, 1 pulse can set the cores in a floor in columns 102 and 104 at 1 and another pulse can set the cores in a floor in columns 103 and 104 at 1.

When the time determined by FFI has expired, decisions are made as to whether the cage is to travel again, and, if so, in which direction it is to travel. This decision is initiated by investigating Whether there is a call above or below the instantaneous position of the cage. On the basis of the result of this investigation, the direction of the travelling is determined according to the following lines of direction: If a call has only been made above the cage, the cage is to travel upwards, if a call has only been made below the cage, the cage is to travel downwards, and

if there is a call both above and below the cage, the cage is to continue in the direction it had when it reached the floor. The cage has to travel if there is a call either above or below the cage otherwise it has to remain in its position.

A call to a floor below the instantaneous position of the cage is the same as a call to a floor above which the cage is located at present. The call is registered in column 101 in the row corresponding to the calling floor and if the cage is above said floor, the core in the same row in column 102 is in the l-state. Thus, if in the same row both cores in columns 101 and 102 are set at 1, then there is a call below the instantaneous position of the cage. This combination is registered in the previously mentioned manner in core 102K by passing current pulses conjunction with'the braking action, since it is not possi-,

ble to make a decision due to action information received only from one floor but information therefore is required from all floors. 1 The cores 102K and 103K are therefore brought into their O-state by 1 which occurs after the cores on all floors having beenunder the influence of I-currents.

If the cage is located at the third iioor, cores 102,3,

103,3 and 1ti3,2 are in their O-state while cores 103,4, 182,2 and 1%,1 are in their l state. If there is'only a call on the third floor or if there is no call at'all, none of the cores itlZK and 103K wi1l be set at. 1; vIn case of a call-on the fourth-floor core 103K will be set at 1, and in the case of call on the first or second floor, core 1 02K will be set at 1.] The first current pulse 1 occurring after the current through kg, has disappeared, will, if there is afcall above or below the'position'o'f the cage, induce a voltage in the conductor K so that FF3 is set and then in turn feeds a signal via conductor 2 to'co nect. the high-speed motor to circuit. 7 j

The same current pulse 1 induces a pulse'in thejconductor if, there is a call below the'cage, and in the conductor 0 if there is a call above thecage. These voltages alter the position of P1 4 in the following manner: If both voltage pulses occur at the same time, noth'- ing will happen, which means that the cage will continue to travel in the direction in which it arrived at the; floor.

' If a pulse is supplied conductor 0 alone indicating that If in a corresponding manner a pulse has been supplied.

only by conductor 0 FF4 will change to its tip-state and allow upward travel of the cage. Change of travelling direction and startof the cage must take place only when the cage stands still and when the period determined by the flip-flop FFl has passed since the last stop of the cage.

When the cage is travelling, one of the flip-flops FFZ and FF3 is set and during the time the cage remains at a floor, FFl is set; each of these three flip-flops sends, when set, a current through the conductor k and thereby through cores 102K and 103K, thereby preventing the cores from being brought into their l-state.

It has previously been mentioned that the state of magnetization of the cores in columns 102, 103 and 104 is dependent on the position of the cage in the lift shaft.

This state of magnetization is controlled by pulses transmitted from the shaft by means of an arrangement consisting of transmitter coils disposed on the cage, which transmit signals to receiver coils disposed in the shaft for each floor and activated inductively by passage of current. Such an arrangement known per se is shown in FIG. 5. A transmitter coil A surrounds the yoke of a U-shaped core U of magnetic material. The entire arrangement is secured to a lift cage or a similar conveying member which is moved inthe directions indicated by arrows which may be horizontally or vertically. Along the path of motion there are different stops which define the intervals of movement and the control has to be such that the cage may stop at the stops or pass the stops according to the publics signals or according to a certain programme or according to a combination thereof. For this purpose signals are transferred to receiver coils M having a core V of magnetic material which coils are arranged in a row in the path of movement of the cage in the case of a lift they are placed in the shaftat the places where information as to the position of the cage is to be supplied to the control system. The coils M must therefore be positioned so that a voltage pulse is induced which produces a current pulse in an associated winding of a memory core so that the core is brought into positive saturation, the l-state, or negative saturation, the O-state, dependent on'the polarity of the current pulse. The state of saturation is determinative in such a case for the orders processed in the control system of current pulses are to be chosen in conformity with this requirement. The sign of the pulses is dependent on the direction of pulses occurring in coil A. The pulse generator of coils A must therefore be so controlled as to produce pulses having a sign being dependent on the direction of movement 'of the cage. However, two transmitter coils may also be provided'which carryv pulses of FIG. 6 illustrates a particularly expedientembodiment ditferent'directions,so that only one coil is always'effective depending on the direction of movement.

" according to which two transmitterlcoils always transmit pulses of opposite polarity. The memory cores in which I the current pulses originating'from the receiver coils will cores are connected with receiver coils M are arranged in the shaft and divide the pathof the cage become effective, are designated by H H These M4, which into a number of intervals. on the cage S,or.the carriage inthe case of horizontal movement, there are mounted two transmitter coils A and A which are passed by ourrent'pulses of different directions so that they produce 'pulseisf'of differentpolarity in the coils M and through the cores H. A pulse originating from the coilA will bring a memory core into its O-state, and. a pulse originating from c'oil'A will bring the same core into its l-state,

tion pulses at the same frequency, said frequency corresponding to said period of time 2, and in such a manner that they commence only after termination of an interro gation pulse and a subsequent fourth pulse and that they terminate before a subsequent interrogation pulse commences, and that the flank steepness of said information pulses is so that no operative signal is transmitted by one of said cores to one of said associated circuits.

7. A control circuit according to claim 1, wherein said means to apply said second information pulses to said cores comprise a push-button panel provided in the lift cage and push-buttons provided at the individual floors between which said lift is movable, said push-buttons being adapted to bring cores of one vertical column of said matrix into their one-state dependent on the floor at which said cage is to be stopped.

8. A control circuit according to claim 1, wherein said means to apply said second information pulses to said cores comprises an arrangement provided in the shaft of said lift, said arrangement being adapted to bring cores of different horizontal rows and of one vertical column of said matrix into their one-state when said cage is above the floor to which the respective row containing said core corresponds, and to bring said cores of said one vertical column into their zero-state, when said cage is at or below the floor to which the respective row containing said core corresponds.

9. A control circuit according to claim 8, wherein said arrangement is furthermore adapted to bring cores of one second vertical column of said matrix into their one-state when said cage is below the floor to which the respective row containing said core corresponds and to bring said cores of said second vertical column into their zero-state, when said cage is at or above the floor to which the respective row containing said core corresponds.

10. A control circuit according to claim 1, wherein said means to apply said second information pulses to said cores comprises an arrangement provided in the shaft of said lift, said arrangement adapted to bring cores of one vertical column of said matrix into their one-state when said cage during its travel along the shaft passes a point p in said shaft in which brakes are to be actuated if the cage is to be stopped at that floor.

11. A control circuit according to claim 9, wherein said arrangement adapted to magnetize said cores of said first and said second vertical column is comprised of a first and a second transmitter coil provided at the cage, and of receiver coils mounted in said shaft in accordance with said individual floors, said transmitter coils adapted to transmit pulses, pulses transmitted by said first transmitter coil being of a polarity opposite to the polarity Y "of pulses transmitted by said second transmitter coil, said coils being spaced from each other so that their respective magnetic fields do not overlap each other, and being adapted to successively pass said receiver coils when said cage travels along said shaft. 7

. 12. A control circuit according to claim 11, wherein at. one time only one of said transmitter coils transmits pulses,i dependent on the direction in which cage travels along said shaft. 9

, 13. A control circuit according to claim 11, wherein each of said coils is adapted to transmit pulses of opposite polarity dependent on the direction in which said cage is moved.

14. A controlcircuit according to claim 9, wherein first and said second vertical columns is comprised of a first and a second transmitter'coil provided at the cage and of a first and second set of receiver coils mounted in said shaft at limits of intervals corresponding to the distance between adjacent floors, only one of said transmitter coils at a time being adapted to transmit pulses, dependent on the direction in which said cage travels, said first coil adapted to influence a receiver coil of said first set and said second coil adapted to influence a receiver coil of said second set, receiver coils of said first and second set located at subsequent limits of an interval being series-connected in pairs so that voltages induced in either of said receiver coils of one pair operate in the same direction.

15. A control circuit according to claim 14, wherein each pair of said series-connected coils is connected through all of the memory cores of one of said first and said second vertical columns, respectively, in such a manner, that a pulse flowing through one of said pairs of coils brings the memory core assigned to the respective coil belonging to said first set of coils and further memory cores assigned to floors on one side of the floor to which the latter mentioned memory core is assigned, into their one state of magnetization, and brings the memory cores assigned to remaining floors into their other, opposite state of magnetization.

16. A control circuit according to claim 2, comprising furthermore third circuits, each of said third circuits associated with one corresponding row, means to generate fourth current pulses and said third circuits having the same frequency and the opposite polarity as said first interrogating pulses and an amplitude at least half as great as and less than the amplitude required to reverse the magnetization of a core, said fourth current pulses being generated at the same period of time as said third pulses, said cores of said first group being passed by a conductor and means being provided to generate sixth interrogating pulses which have the same frequency as said second information pulses and have an amplitude capable of both cancelling the ampere windings produced by said third and said fourth current pulses and capable of producing suificient ampere windings to reverse the magnetization of said memory cores, said sixth pulses passing through said conductor passing said cores of said first group, and commencing during the period when said third pulses pass said second circuits associated with the first and the last vertical column of said matrix.

17'. Acontrol circuit according to claim 16, wherein 1 cores of said remaining groups are passed by a conductor and wherein means are provided to generate seventh interrogating pulses having the same frequency as said first interrogating pulses and being displaced in relation to said first interrogating pulses generated in a first circuit associated with the first floor by a period of time t References Cited by the Examiner UNITED STATES PATENTS 9/57 Hall et al. 187-29 6/62 Suozzo et al. 187-29 OTHER REFERENCES 1960, TK7888.3-M4C.5, pages 92, 93}

ORIS L. RADER, Primary Examiner, 

